I need to have English (US) and no compose key for the system, and I'd like English (Dvorak alternative international no dead keys) + Caps Lock as the compose key for myself. How can I set this up?

I tried setting dvorak-alt-intl in lxkeymap, but it only worked until I logged in again. I also tried to set @setxkbmap -option compose:caps in ~/.config/lxsession/LXDE/autostart, but that didn't work after logging in again.